Superheater assembly



May 14, 1935. c. s; TURNER v SUPERHEATER ASSEMBLY I Original Filed Feb.1, 19.32 2 Sheet-Sheet 1 INVENIOR [fi yzgs 6) ATTORNEYS May 14, 1935. Q5 URNE SUPERHEATEB ASSEMBLY Original Filed Feb. 1, 1952 ZIS I'wetS-Sheet 2 Zara/56a) Charles S. 72153 ATTORNEYS Patented May 14, 1935UNITED STATES 2,000,907 suraanmm ASSEMBLY Charles s. Turner, Detroit,Mich.

Applicationl ebruary 1, 1932, Serlal No. 590,1 Renewed October 6, 1934.7 Claims. (01. 122-473) of which a bank or group of superheater tubesmay be installed in positions ofmaximum radiant heat exposure, withtheir terminal fittings or connections adequately protected against adegree of heat, which, under frequently encountered operatingconditions, would cause the rapid deterioration thereof, while 'thesuperheater tubes themselves will, because of their special and pre-"ferred construction, last an indefinitely longer time without noticeableimpairment.

These terminal fittings, which are usually of cast, one-piececonstruction, are of-course designed to handle, receptively at one endof their respective superheated tubes and distributively at the otherend thereof, not only the supply of steam whose superheating is desired,but as well the cooling fluid column whose surrounding walls aregenerally integrated with the wall of the superheater tube proper, and,if the superheater units are, as well, equipped with integrated cleaningor blower jet pipes, the cooling influence of the fluids passing throughone or both ofthese is suflicient to protectively influence thetemperature of the superheater tube walls against unduly rapid heatimpairment.

This, for the reasons above stated, not being the case as to thegenerally cast terminal flttingsof the several superheater tubes,particularlyif either the cooling column or the sootblower elements arenot active, special protective constructions for these terminal fittingsbecome necessary. My. preferred construction for eifecting thisillustrated in the accompanying drawings, wherein Figure l isan'elevation'al view, partly in sec tion, of a tubular boilerinstallation equipped as well with my superheater protective elements.

Figure 2 is a plan view from above, showing a plurality of superheatertubes in their extent across the flue space in a furnace chamber, andemphasizing the positioning of the, terminal flttings of the superheatertubes behind both the baflles and whatever number of boiler tubes it maybe desired to position them.

Figure 3 is an elevational view, partly in section showing the endfittings of a superheater tube protected at one end, as in Figure 1behind a baifle and plurality of boiler tubes, and at the other .end bya wall of the furnace, through which the other end of the superheatertube extends Figure 4 is a sectional view illustration of a preferredform of construction of companionterminal fittings for the superheatertubes, whose protection against undue and destructive thermal conditionsis desired.

Figure 5 is a longitudinal sectional view of the preferredform ofterminal fitting shown cross- I sectionally in Figure 4, along the line5-5 thereof.

A represents the walls of the furnace, over whose central heat fluespace B are obliquely positioned boiler tube elements C. For purposes ofguidance of the gases of combustion through suc- 10 ces'sive tube banks,the boiler drums as G, baflles D, which generally are immediately behindone or more of the boiler tubes as C; are positioned on either side, asshown, forming in effect a more or less constricted throat about theflue space B. 15 For superheating purposes, a plurality of superheatertubes, as E and F, are positioned angularly, though much more nearly ina horizontal position than the boiler tubes C, across the flue space B,ofcourse. much nearer the heat source 20 than the boiler tubes C, anddirectly in the path of the upwardly proceeding heat units. Each of thisseries of superheater tubes E or F, cooperatively with its correspondingsupply tube as E and F, of course are components of a ,U-shaped 25circulatory system, and the advantage of having each superheater" tubelying at an angle to the horizon as shown lies in the fact that each legof the circulatory system as thus constituted does its share incontributing toward eifective circulation,-each superheater tubeconstituting the hot leg of the U-shaped structure, while its connectedfeeder or supply tube constitutes the cold leg; 4 without such anarrangement, that is to say, if the superheater tubes'were positionedhorizontal- 1y across the flue space B, the action of some: such elementas agpump would be necessary to keep up an adequate degree ofcirculation, aswell as to determine the direction 01' circulation.

This alteration of the superheater tubes of 40 the series E and F isbrought out with special clearness in plan Figure 2, wherein it willalso be noted that inthe showings of the terminal flttingsL and N theupper or right-hand ends of the several superheater elements E havetheir steam supply tubes E shown in full lines and the superheaterelements of the series F similarly have their steam supply tubes F shownin full lines, the position, on the lower side of the fltting of eitherseries of its corresponding steam 5 discharge pipe being indicated bydotted circles at E and F respectively; these latter elements are ofcourse shown elevationally in full lines in Figure 1.

As stated, and as brought out particularly in u cross-sectional Figure4, these superheater tube units have, in addition to the space J throughwhich the superheated steam passes, an integrated cooling column, as K,which of course extends lengthwise of the superheater tube structuresuperheater tubes of the series E or F in Figure 1.

Though of course there may be as many super-' heater tubes T as may bedesired, or the depth of the furnace chamber may permit, they are notalternated, as in the instance of the first described constructionbecause 01 their being but one bank or inclined boiler tubes; and all ofthe superheater tubes T extend in the same oblique direction. The lowerend of each superheater tube T of this series now being describedextends relatively close assemblage by the receiving fitting, as L,while the fitting N, at the other end of the superheater tube, effectsthe distribution of the fluid elements respectively handled by theseveral guiding columns to their respective piping connectionsappurtenant to the furnace as a whole. Cooling .water connections,generally with a common supply pipe for all of the superheater units,are shown at M.

The separate chambers J and K of each ter- 7 radiant heat action to thesame degree as the superheater tubes E or F themselves. If, however, oneor both of these auxiliary, heat-modifying appurtenances are. notfunctioning, as is fretubes, as C, is of such markedly lower tempera-'ture, even with the furnace working at capacity, that with the terminalfittings, as L and N, positioned thus, they in most cases attain only atemperature which at the worst is much more slowly destructive of thefittings than would be the case ii',they were, like the superheatertubes,exposecl to direct'radiant heat. In most cases the positioning ofthe terminal fittings behind the baiiles and behind the first or outerrow of ordinary boiler tubes, as C, is-generally sufiicient for theadequate protection of the terminal fittings L and N, but in caseunusually high heat conditions are through the verticaLfurnace wall W,so that this latter protects the lower terminal fitting, as V, againstundue heating just as the baffle S, and the s veral rows of boiler tubesQ protects the upper erminal fitting X. The steamsupply and outletconnections of the terminal fittings are the same as already .describedin connectio with the explanation of Figure 1. I

What I claim isz 1-. In a furnace having baiile' walls, in combinationwith a plurality of spacedly disposed banks of boiler tubes flanking anintermediate space between said baille walls through which rising heatunits and gases of combustion travel, a fluid-cooled superheater elementextending across said space and inclined from the horizontal, havingseparate steam and water passages therein and metallic heat bridgingportions connecting and integral'with the walls of each, inlet andoutlet terminals connecting said passages with the steam and waterspaces respectively of the boiler, the water inlet terminal thereofbeing positioned below the water outlet terminal, whereby a convectioncurrent is induced in the water channel of the superheater element, andboth the inlets and outlets being located outside said intermediatespace and baflle walls.

2. Incombination with a furnace having baifle wallsand an intermediateflue gas passage, a I

said passage, water-cooled superheated tube as-' semblies extendinglaterally across said passage between opposite units of each tube groupand inclined from the horizontal, separate steam and water channels ineach of such tube assemblies and having walls, metallic heat bridgesintegral with and connecting the walls;a water inlet in the lower end ofeach assembly, and a water outlet at its higher end, said inlets andoutlets being arranged outside said bafllle walls and intermeto be dealtwith, a still further degree of protection can be secured by positioningthe fittings L and N behind the second row of ordinary boiler tubes, asC, or even further back as for example, behind the still more remotetube rows as C? and C. In any event, and according to the particularcircumstances of each case, a marked heat. dif-.

ferential between the thermal conditions to which the superheater tubes,as E and F, are intention-- ally exposed, and those to which theterminal fittings L and N, often unprotected by cooling colhere shownpositioned behind a plurality of the boiler tube rows, and between theunits of these rows and protectedlythrough the baflie S extend thesuperheatertubes 'I with their terminal fittings V and X in the sameoblique position as the diate passage. I

3. In combination with a furnace incorporating steam generating meansand having a combustion chamber, superheating means comprising steam andwater conduit portions arranged closely appurtenant one'another andextending across the combustion chamber at an angle to the horizontal,integral heat bridging portions connecting 4. In a steam boiler, incombination with a water conduit portions arranged adjacent one Ianother and extending across: said passage at an angle to thehorizontal, integral heat bridging portions connectingsaidsteam-andwater conduit portions, said conduits being extended through said walls,and inlet-and outlet portions conected to the 9,000,907 5. Incombination with a steam boiierhsving walls deiining'a passage thro lwhich heated gases of combustion pass, regulatable steam superheating'means comprising separate metallic steam and water conduits extendingacross said passage at an angle relatively to the horizontal and inclose proximity, and integral metallic heat brid ing portions connectingsaid steam and water conduits. 3

6. In combination with a steam boiler having walls defining a passagethrough which heated gases 0! combustion pass, regulatable steamsuperheating means comprising separate metallic steam and water conduitsextending across said e at an angle relatively to the horizon and inclose proximity; and metallic heat bridging means-extendingsubstantially the length of the eiiective portions of said conduits andintegral with both the steam and water conduit portions.

7. Incombination withasteamboilerhaving walls defining a e through whichheated gases of combustion pass. regulatable steam super-heating meanscomprising separate metallic steam and water conduits extending acrosssaid passage at an amle relatively to the horizon and in close proximityto each other, metallic heat bridging portions extending substantiallythe entire effective length 01' said conduits and integral with both thesteam and water conduit portions, said conduit portions being projectedthrough the walls, and inlet and outlet portions connected to saidconduit portions outside the walls.

CHARLB$W

